These are the headlines at https://www.sciencealert.com/jwst-confirms-distant-galaxy-was-murdered-by-a-black-hole …. observations of an ancient galaxy that was declared dead now have it confirmed by the James Webb Space Telescope. No new stars are being formed, is one sign of lifelessness, it would seem – but who or what was the culprit? Astronomers, they continue, now know what happened. They sound confident.
Supermassive black holes live at the heart of galaxies and they play a big role in the shape of that galaxy in many ways. The black hole is thought to create powerful active galactic nuclei at the core of the galaxy- its heart. As the black hole claws material towards it the material forms an accretion disk. The material is also super heated to extremely high temperatures and gives off energy across the electromagnetic spectrum. This causes the active galactic nuclei to become really powerful and energetic. We are then told they have the power to disrupt the supply of cold star forming gases and dramatically slow the star formation rate. They blow winds of star forming gases out of their galaxies. This is the murdering process it would seem.
Getting back to the ancient galaxy that was the target at this link, they note it formed not too long after Big Bang. It seems it is not the only galaxy that appears to have stopped forming new stars. Previous observations using other telescopes show that galaxies have fast outflowing winds of gas, and the gas is hot. The murdered galaxy is still expelling large quantities of hot gas, or plasma, at velocities high enough to escape the galaxy completely. James Webb added another layer as it observed that the gas being expelled also included cold gas. Critically, without cold gas a galaxy would struggle to form stars. It seems there is more gas being expelled than the amount needed to form new stars. We found the culprit, they say, the black hole is killing the galaxy and keeping it in a dormant state by cutting off the source of food the galaxy requires to form new stars.
Having got that onboard we read at https://phys.org/news/2024-08-star-destroyed-supermassive-black-hole.html … we have a computer driven simulation of a star destroyed by a supermassive black hole. The first of its kind.
At https://www.livescience.com/physics-mathematics/quantum-physics/stephen-hawking-s-black-hole-radiation-paradox-could-finally-be-solved-if-black-holes-aren-t-what-they-seem … a new study suggests that black holes may not be the featureless, structureless entities that Einstein’s general theory of relativity predicted them to be. Instead, the cosmic monsters might be bizarre quantum hypothetical celestial bodies that differ in crucial ways that could potentially resolves the infamous Hawking radiation paradox. This paradox arises, we are told, because the theoretical radiation emitted by a black holes event horizon seemingly carries no information about the matter that formed the black hole. This contradicts a fundamental principle of quantum mechanics stating that information cannot be destroyed. Frozen stars mimic black holes, ultra compact astrophysical objects that are free of singularities, lack a horizon, but yet mimic all of the observatble properties of black holes. If they actually exist, it continues, they would indicate the need to modify in a significant and fundamental way Einstein’s theory of general relativity. Cosmology is becoming interesting – at last. Are black holes always black holes. How do frozen stars perform?